Data storage devices (DSDs) are often used to record data on or to reproduce data from a recording media. DSDs can include different types of non-volatile memory (NVM) for storing data. One type of NVM includes a rotating magnetic disk. In addition to a magnetic disk, a DSD can include a second type of NVM, such as a solid state NVM. DSDs including both a magnetic disk and a solid state NVM are often referred to as a hybrid drive. Because different types of NVM have different performance characteristics, strategies for storing data may vary depending on the type of NVM used.
One example is during a hibernate process of a computer system. Before turning off power, a computer system may perform a hibernate process to preserve a state of the computer system in an NVM. When power is later restored to the computer system, an operating system of the computer system performs a resume process to restore the computer system to the same state as before hibernation. A solid state NVM, such as flash memory, should be generally capable of a relatively quick resumption after hibernation because of the high read transfer rate associated with flash memory.
Unfortunately, flash memory suffers from endurance issues that cause flash memory to wear out from repeated use. As a result, some operating systems implement a computationally intensive compression of hibernate data to reduce the size of the hibernate data in an effort to reduce wear on the flash memory caused by repeatedly storing hibernate data. Although a high compression of hibernate data may help preserve the life of flash memory, such high compression can undesirably prolong the time it takes to resume from hibernation since the hibernate data must be decompressed from a highly compressed state.
Magnetic disks generally do not suffer from the endurance issues noted above for flash memory and therefore an operating system may not compress hibernate data stored to a magnetic disk as highly as hibernate data stored to a flash memory. However, magnetic disks suffer from a relatively long time to ready while the magnetic disk “spins up,” resulting in slower transfer rates than for flash media. As with the prolonged resumption discussed above for flash memory, the slower transfer rate of a magnetic disk can result in an undesirable long resumption time.